I am looking for a closed or noise canceling headphone system that is good for mainly jazz but won't torch the few songs of classic/modern rock that I have in my library. I DO NOT listen to rap, hip hop or dubstep so I don't need an over powering bass. I would also like to bring these headphones in the car when I go on road trips with my friends but I don't plan to go jogging or even where them outside of a car or my house. I really would prefer not to have to buy an amp for these puppies. I'm a saxophone player and am often looking to hear the saxophone in the band so please take that into consideration as well (mainly meaning I'd like to be able to single out certain sounds in the band). I would prefer the headphones not to drop of the deep end with any specific sound (for ex. great bass but squeaky and annoying high, etc.) Lastly, I would like to wear these puppies for a few hours at a time so please have them be comfortable. I don't like having to stop listening to my music because the headphones are killing my ears.

Thanks so much. Please explain the pros and cons of each (specifically lows, mids, highs, soundstage and comfort)

The SRH940 is a very good closed headphone. I would say close to neutral. Very good detail, clarity and excellent vocals. It's a bit light on bass, but should do very well based on your music and requirements. Fit and comfort were both very good, but I only had it on for about 30 minutes. The ear cups are quite large though, so I wouldn't expect any comfort issues. And, isolation was about average if memory serves. Unfortunately, I have not heard the ATH900, so I can't comment on that one.

Another great headphone that may meet your requirements is the AKG K550. I own the K550 and actually slightly prefer it over the SRH940. The only potential hiccup with the K550 is possibly fit/seal issues. It seems like at least half the people that try it can't get a good seal on the cups. Comfort on the ear cups is excellent, but I do get some very mild discomfort from the headband during extended listening sessions. Just make sure you try it first...

I've owned the Shure's for the better part of year and what gradually happened for me was that I stopped listening to my Beyerdynamic and Senn cans in favor of the 940s. I listen to everything except rap / hip-hop (blech) as well. I find the Shares amazing for detailed vocals, and great for most instrumentals: especially folk strings (guitar, banjo, fiddle). I haven't listened to a ton of jazz recently, but tried Brubeck's "Time Out," Coltrane's "Giant Steps," and Davis' "Kind of Blue" when I first got them and was very impressed.